Re: USB cards for PWS 433au
On Sat, Jun 23, 2012 at 08:35:38PM -0500, Bob Tracy wrote:
> On Sun, Jun 24, 2012 at 11:59:15AM +1200, Michael Cree wrote:
> > On 23/06/12 18:43, Bob Tracy wrote:
> > > I recently retired an old AMD K6-III/450 system that had a serviceable
> > > USB controller in it, so I tried transplanting it to my Alpha. The
> > > kernel seems to detect it just fine and load the appropriate drivers,
> > > but there's evidently a conflict of some kind between the USB card and
> > > my Radeon 7500.
> > The infamous PWS PCI DMA hardware bug maybe?
> > Are you putting the USB card in the 64 bit or 32 bit slot? I think the
> > recommendation is *not* to put anything involving data storage in the 64
> > bit slots of any 1st generation PWS.
Five card slots total. Top to bottom, we have three ISA-or-32-bit-PCI
slots, and then the two 64-bit PCI slots. The QLOGIC SCSI card and the
VIA USB card were in the second and third 32-bit slots repectively, and
my Radeon 7500 was in a 64-bit slot. I tried moving the USB card to the
top 32-bit PCI slot (reduced top-side component clearance due to a
wiring harness, so I couldn't put the video card there), and moved the
video card to the slot where the USB card was. No difference. Sliced-up
my hand on the sharp sheet metal in the case, so I'll let things cook a
while before going back in and removing the USB card (to see if the video
strangeness goes away). If it does, I've got a machine with a NCR USB card
in it that I'll try in the Alpha, because I'm pretty sure the VIA card will
work just fine in that other machine.